The invention relates to a control apparatus for the variation of the onset of supply by a fuel injection pump having an adjustment piston engaging the piston cam drive, the adjustment piston under rpm-dependent pressure being adjustable counter to a restoring force by a fluid located in a work chamber of the adjustment piston, and an assembly for prolonging the supply time and at least during pump supply on the basis of the restoring and reactionary force including displacing the adjustment piston counter to the fluid pressure.
One means of damping noise development in Diesel engines consists in the prolongation of the injection duration during idling or at relatively low partial-load. In a known fuel injection system, a portion of the fuel supplied by the injection pump piston flows off unutilized, for the purpose of prolonging the injection time, so that the portion of fuel proceeding to injection must be supplied for a relatively longer time, in order to maintain the rpm. This known means of regulation is relatively expensive, and there is a certain difficulty in regulating the quantity of fuel, because the quantity which flows off must also be taken into account in the regulation which occurs by means of shutoff control or shutdown control. These disadvantages are more serious than may appear at first sight, because in the case of feeding in any engine characteristics for regulation purposes, as is increasingly necessary, a corresponding amount of attention must also be paid to this outflow quantity, serving the purpose of smooth running, with all the correction transducers which are necessary to achieve this.